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Vmere.1
Associate III
November 25, 2021
Solved

Hard fault not occurring? Trying to create intentional hard fault

  • November 25, 2021
  • 7 replies
  • 4043 views

this may be little weird asking to the big guys. But I'm learning how to produce hard fault so as to debug it again using registers. Also I tried initializing np with NULL. but still no success

/* USER CODE BEGIN Header */
/**
 ******************************************************************************
 * @file : main.c
 * @brief : Main program body
 ******************************************************************************
 * @attention
 *
 * <h2><center>&copy; Copyright (c) 2021 STMicroelectronics.
 * All rights reserved.</center></h2>
 *
 * This software component is licensed by ST under BSD 3-Clause license,
 * the "License"; You may not use this file except in compliance with the
 * License. You may obtain a copy of the License at:
 * opensource.org/licenses/BSD-3-Clause
 *
 ******************************************************************************
 */
/* USER CODE END Header */
/* Includes ------------------------------------------------------------------*/
#include "main.h"
 
/* Private includes ----------------------------------------------------------*/
/* USER CODE BEGIN Includes */
 
/* USER CODE END Includes */
 
/* Private typedef -----------------------------------------------------------*/
/* USER CODE BEGIN PTD */
 
/* USER CODE END PTD */
 
/* Private define ------------------------------------------------------------*/
/* USER CODE BEGIN PD */
/* USER CODE END PD */
 
/* Private macro -------------------------------------------------------------*/
/* USER CODE BEGIN PM */
 
/* USER CODE END PM */
 
/* Private variables ---------------------------------------------------------*/
UART_HandleTypeDef hlpuart1;
 
/* USER CODE BEGIN PV */
 
/* USER CODE END PV */
 
/* Private function prototypes -----------------------------------------------*/
void SystemClock_Config(void);
static void MX_GPIO_Init(void);
static void MX_LPUART1_UART_Init(void);
/* USER CODE BEGIN PFP */
 
/* USER CODE END PFP */
 
/* Private user code ---------------------------------------------------------*/
/* USER CODE BEGIN 0 */
 
/* USER CODE END 0 */
 
/**
 * @brief The application entry point.
 * @retval int
 */
int main(void)
{
 /* USER CODE BEGIN 1 */
 uint32_t * NP;
 /* USER CODE END 1 */
 
 /* MCU Configuration--------------------------------------------------------*/
 
 /* Reset of all peripherals, Initializes the Flash interface and the Systick. */
 HAL_Init();
 
 /* USER CODE BEGIN Init */
 
 /* USER CODE END Init */
 
 /* Configure the system clock */
 SystemClock_Config();
 
 /* USER CODE BEGIN SysInit */
 
 /* USER CODE END SysInit */
 
 /* Initialize all configured peripherals */
 MX_GPIO_Init();
 MX_LPUART1_UART_Init();
 /* USER CODE BEGIN 2 */
 
 /* USER CODE END 2 */
 
 /* Infinite loop */
 /* USER CODE BEGIN WHILE */
 while (1)
 {
 /* USER CODE END WHILE */
 
 /* USER CODE BEGIN 3 */
	 if(HAL_GPIO_ReadPin(B1_GPIO_Port, B1_Pin) == GPIO_PIN_SET)
	 {
		 *NP =35;
	 }
 }
 /* USER CODE END 3 */
}
 
/**
 * @brief System Clock Configuration
 * @retval None
 */
void SystemClock_Config(void)
{
 RCC_OscInitTypeDef RCC_OscInitStruct = {0};
 RCC_ClkInitTypeDef RCC_ClkInitStruct = {0};
 RCC_PeriphCLKInitTypeDef PeriphClkInit = {0};
 
 /** Configure the main internal regulator output voltage
 */
 HAL_PWREx_ControlVoltageScaling(PWR_REGULATOR_VOLTAGE_SCALE1_BOOST);
 /** Initializes the RCC Oscillators according to the specified parameters
 * in the RCC_OscInitTypeDef structure.
 */
 RCC_OscInitStruct.OscillatorType = RCC_OSCILLATORTYPE_HSI;
 RCC_OscInitStruct.HSIState = RCC_HSI_ON;
 RCC_OscInitStruct.HSICalibrationValue = RCC_HSICALIBRATION_DEFAULT;
 RCC_OscInitStruct.PLL.PLLState = RCC_PLL_ON;
 RCC_OscInitStruct.PLL.PLLSource = RCC_PLLSOURCE_HSI;
 RCC_OscInitStruct.PLL.PLLM = RCC_PLLM_DIV4;
 RCC_OscInitStruct.PLL.PLLN = 85;
 RCC_OscInitStruct.PLL.PLLP = RCC_PLLP_DIV2;
 RCC_OscInitStruct.PLL.PLLQ = RCC_PLLQ_DIV2;
 RCC_OscInitStruct.PLL.PLLR = RCC_PLLR_DIV2;
 if (HAL_RCC_OscConfig(&RCC_OscInitStruct) != HAL_OK)
 {
 Error_Handler();
 }
 /** Initializes the CPU, AHB and APB buses clocks
 */
 RCC_ClkInitStruct.ClockType = RCC_CLOCKTYPE_HCLK|RCC_CLOCKTYPE_SYSCLK
 |RCC_CLOCKTYPE_PCLK1|RCC_CLOCKTYPE_PCLK2;
 RCC_ClkInitStruct.SYSCLKSource = RCC_SYSCLKSOURCE_PLLCLK;
 RCC_ClkInitStruct.AHBCLKDivider = RCC_SYSCLK_DIV1;
 RCC_ClkInitStruct.APB1CLKDivider = RCC_HCLK_DIV1;
 RCC_ClkInitStruct.APB2CLKDivider = RCC_HCLK_DIV1;
 
 if (HAL_RCC_ClockConfig(&RCC_ClkInitStruct, FLASH_LATENCY_4) != HAL_OK)
 {
 Error_Handler();
 }
 /** Initializes the peripherals clocks
 */
 PeriphClkInit.PeriphClockSelection = RCC_PERIPHCLK_LPUART1;
 PeriphClkInit.Lpuart1ClockSelection = RCC_LPUART1CLKSOURCE_PCLK1;
 if (HAL_RCCEx_PeriphCLKConfig(&PeriphClkInit) != HAL_OK)
 {
 Error_Handler();
 }
}
 
/**
 * @brief LPUART1 Initialization Function
 * @param None
 * @retval None
 */
static void MX_LPUART1_UART_Init(void)
{
 
 /* USER CODE BEGIN LPUART1_Init 0 */
 
 /* USER CODE END LPUART1_Init 0 */
 
 /* USER CODE BEGIN LPUART1_Init 1 */
 
 /* USER CODE END LPUART1_Init 1 */
 hlpuart1.Instance = LPUART1;
 hlpuart1.Init.BaudRate = 115200;
 hlpuart1.Init.WordLength = UART_WORDLENGTH_8B;
 hlpuart1.Init.StopBits = UART_STOPBITS_1;
 hlpuart1.Init.Parity = UART_PARITY_NONE;
 hlpuart1.Init.Mode = UART_MODE_TX_RX;
 hlpuart1.Init.HwFlowCtl = UART_HWCONTROL_NONE;
 hlpuart1.Init.OneBitSampling = UART_ONE_BIT_SAMPLE_DISABLE;
 hlpuart1.Init.ClockPrescaler = UART_PRESCALER_DIV1;
 hlpuart1.AdvancedInit.AdvFeatureInit = UART_ADVFEATURE_NO_INIT;
 if (HAL_UART_Init(&hlpuart1) != HAL_OK)
 {
 Error_Handler();
 }
 if (HAL_UARTEx_SetTxFifoThreshold(&hlpuart1, UART_TXFIFO_THRESHOLD_1_8) != HAL_OK)
 {
 Error_Handler();
 }
 if (HAL_UARTEx_SetRxFifoThreshold(&hlpuart1, UART_RXFIFO_THRESHOLD_1_8) != HAL_OK)
 {
 Error_Handler();
 }
 if (HAL_UARTEx_DisableFifoMode(&hlpuart1) != HAL_OK)
 {
 Error_Handler();
 }
 /* USER CODE BEGIN LPUART1_Init 2 */
 
 /* USER CODE END LPUART1_Init 2 */
 
}
 
/**
 * @brief GPIO Initialization Function
 * @param None
 * @retval None
 */
static void MX_GPIO_Init(void)
{
 GPIO_InitTypeDef GPIO_InitStruct = {0};
 
 /* GPIO Ports Clock Enable */
 __HAL_RCC_GPIOC_CLK_ENABLE();
 __HAL_RCC_GPIOF_CLK_ENABLE();
 __HAL_RCC_GPIOA_CLK_ENABLE();
 __HAL_RCC_GPIOB_CLK_ENABLE();
 
 /*Configure GPIO pin Output Level */
 HAL_GPIO_WritePin(LD2_GPIO_Port, LD2_Pin, GPIO_PIN_RESET);
 
 /*Configure GPIO pin : B1_Pin */
 GPIO_InitStruct.Pin = B1_Pin;
 GPIO_InitStruct.Mode = GPIO_MODE_IT_RISING;
 GPIO_InitStruct.Pull = GPIO_NOPULL;
 HAL_GPIO_Init(B1_GPIO_Port, &GPIO_InitStruct);
 
 /*Configure GPIO pin : LD2_Pin */
 GPIO_InitStruct.Pin = LD2_Pin;
 GPIO_InitStruct.Mode = GPIO_MODE_OUTPUT_PP;
 GPIO_InitStruct.Pull = GPIO_NOPULL;
 GPIO_InitStruct.Speed = GPIO_SPEED_FREQ_LOW;
 HAL_GPIO_Init(LD2_GPIO_Port, &GPIO_InitStruct);
 
 /* EXTI interrupt init*/
 HAL_NVIC_SetPriority(EXTI15_10_IRQn, 0, 0);
 HAL_NVIC_EnableIRQ(EXTI15_10_IRQn);
 
}
 
/* USER CODE BEGIN 4 */
 
/* USER CODE END 4 */
 
/**
 * @brief This function is executed in case of error occurrence.
 * @retval None
 */
void Error_Handler(void)
{
 /* USER CODE BEGIN Error_Handler_Debug */
 /* User can add his own implementation to report the HAL error return state */
 __disable_irq();
 while (1)
 {
 }
 /* USER CODE END Error_Handler_Debug */
}
 
#ifdef USE_FULL_ASSERT
/**
 * @brief Reports the name of the source file and the source line number
 * where the assert_param error has occurred.
 * @param file: pointer to the source file name
 * @param line: assert_param error line source number
 * @retval None
 */
void assert_failed(uint8_t *file, uint32_t line)
{
 /* USER CODE BEGIN 6 */
 /* User can add his own implementation to report the file name and line number,
 ex: printf("Wrong parameters value: file %s on line %d\r\n", file, line) */
 /* USER CODE END 6 */
}
#endif /* USE_FULL_ASSERT */
 
/************************ (C) COPYRIGHT STMicroelectronics *****END OF FILE****/

Im pressing the button multiple times. It is going in the while loop and also into the if condition and executing. But I want hard fault. What can I do here? Am I missing something?

Thanks in advance.

This topic has been closed for replies.
Best answer by Tesla DeLorean

0 is a valid address, 0x20CDCDCD wouldn't be.

Try doing a read via an uint64_t or double pointer which intentionally misaligned.​

7 replies

November 25, 2021

Sometimes I have had this failure Hard fault when the program extrapolates the index of an array variable.

Hard Fault: is caused by Bus Fault, Memory Management Fault, or Usage Fault if their handler cannot be executed

Analyzing HardFaults on Cortex-M CPU:

https://www.segger.com/downloads/application-notes/AN00016#:~:text=Hard%20Fault%3A%20is%20caused%20by,execp%2D%20tion%20handler%20is%20executed.

ST Employee
November 25, 2021

Hi @Vmere.1​ 

Another to produce a HardFault is to divide by 0 which is an Usage Fault.

Best Regards,

Gwénolé

Tesla DeLorean
Tesla DeLoreanBest answer
Guru
November 25, 2021

0 is a valid address, 0x20CDCDCD wouldn't be.

Try doing a read via an uint64_t or double pointer which intentionally misaligned.​

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Vmere.1
Vmere.1Author
Associate III
November 25, 2021

Thanks man. I found it. And thanks Gwenole, yeah divide by zero can also work but only if the divide by zero is activated in the CCR register, which I checked accidentally. and divide by zero is not activated.

But Tesla deLorean is rught NULL is a valid address in ARM. And i tried the value something like 0xcccccccc and I got the fault.

Vmere.1
Vmere.1Author
Associate III
November 25, 2021

Thank you. Just one more question. is divide by zero should be activated or not? usual scenarios (I work in a project which is new ) and I noticed that DIV/zero is not activated.

waclawek.jan
Super User
November 25, 2021

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